Researchers at Linköping University and the KTH Royal Institute of Technology in Sweden, have created the first functioning transistor made of wood. This represents an early step in the development of biodegradable electronics.
The researchers started with balsa wood and removed the lignin that makes wood strong and rigid. This created cellulose fibers with hollow channels that were then filled with a conductive polymer known as PEDOT: PSS. The resulting component could regulate an electric current passing through it, provide a consistent flow of electrons at a selected output level, and switch power on and off.
There’s still a long way to go. The bulky wooden transistor took a second to switch off and up to five seconds to turn on. However, the wooden transistor marks progress toward biodegradable electronics and the goal of reducing e-waste.
The full research report was published in Proceedings of the National Academy of Sciences and can be found here.